MANILA -- Criminal Investigation and Detection Group (CIDG) director Chief Supt. Benjamin Magalong on Wednesday said they have started investigating allegations of overpricing and use of substandard materials in the construction of bunkhouses in areas hit by super typhoon "Yolanda."

According to Magalong, the investigation started even before post-Yolanda rehabilitation czar Panfilo Lacson sent them a formal request to investigate the alleged use of substandard materials, and collusion between contractors and a politician to pocket a 30- or 35-percent kickback on the construction of the units.

He said the CIDG will meet with construction experts to get their opinion on the materials used in the temporary shelters for typhoon survivors.

Magalong said the CIDG will help assess whether the allegations are true or not.

As of now, 126 units of bunkhouses have been built. The construction of other 96 bunkhouses is still ongoing.

Lacson earlier said he has also tapped the assistance of civil engineers and architects to confirm if some bunkhouses being constructed are substandard or under the specifications set by the Department of Public Works and Highways (DPWH).

The bunkhouses should be able to withstand typhoons as strong as Yolanda, he said, adding that the government's goal is to build better and safer shelters for the affected residents.

He said once they have gathered enough evidence, they will file a case against the politician before the Ombudsman.